NPDES Municipal Surface Water Discharges

Municipal Wastewater Discharge Permits

The municipal surface water discharge permit is a combined state and federal permit under the National Pollutant Discharge Elimination System (NPDES). This permit is issued for sewage treatment plants and some water treatment plants that discharge to State surface waters. The permit is designed to protect the quality of the body of water receiving the discharge. Anyone who discharges wastewater to surface waters may need a surface water discharge permit. Applicants include municipalities, counties, federal facilities, schools, and commercial water and wastewater treatment plants, as well as treatment systems for private residences that discharge to surface waters.

Additionally, an industrial discharge to a municipal wastewater collection system may require a pretreatment permit. 

Reclaimed Water Guidance​

The Department encourages the use of reclaimed water as an alternative to discharge.  Reclaimed water is categorized into four water quality Classes (I-IV) which govern their potential uses.  Links below provide guidance for reclaimed water based on the water quality Class.

Wastewater Permits Interactive Search Portal

The Wastewater Permits Program maintains an interactive search portal which allows the general public to search for permits by facility name, location, permit number, and/or permit type.  Once the desired permit entry is located, users have the opportunity to click the "More Info" button to display a list of available documents for download including permit applications, final permits and fact sheets, draft permits up for public comment, and general permit registration letters. 

Electronic Reporting Rule 

On Decembet 21, 2015, the U.S. Environmental Protection Agency promulgated a final rule to modernize Clean Water Act reporting for municipalities, industries, and other facilities by converting to an electronic data reporting system (40 CFR 127.16). The final rule requires all National Pollution Discharge Elimination System (NPDES) regulated entities to electronically submit Discharge Monitoring Reports (DMRs) effective December 21, 2016. 

Before you can submit official DMRs online using NetDMR, you must attend a training webinar, successfully complete account set-up, and submit example monitoring results electronically.  

Municipal Surface Water Discharge Permit Forms

Certification of Workers' Compensation Insurance Coverage

Pursuant to Section 1-202 of the Environment Article, before MDE may issue a license or permit to a business that might employ a covered employee, the business shall submit to MDE a valid workers' compensation insurance policy or binder. Businesses that are exempt from having to provide workers' compensation insurance under applicable provisions of the Labor & Employment Article may need to submit a Certificate of Compliance. (MDE/WMA/PER.069) 


Contact Information

Please contact the Department at (410) 537-3671 for more information.


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